Syuksok Formation

Syuksok Fm

Period:

Cretaceous

Age Interval:

upper Turonian – Santonian, CK2, CK5a, CK8, CK9, C11

Province:
Chatkal-Kuramin Region

Type Locality and Naming

Along the Suk-Suk kolhoz, Pri-Tashkent district, Kazakhstan. G.A. Belenky, 1966 (96, p.105). Stratotype near the Suk-Suk kolhoz, 10km east of the Dzhilga railway station, 45 km north of the city of Tashkent.

Synonym: Suksuk Suite, Сюксокская св.

Lithology and Thickness

The suite is characterized by the predominance of pink, pinkish-red, and red sandstones and sands with interlayers of conglomerates containing bone remains of turtles, dinosaurs, and crocodiles. In the stratotype section, the suite is divided into lower and upper sub-suites. The lower sub-suite is represented by fine-grained, orange sands, fine- and coarse-grained quartz sandstones, pink with interlayers of brown clays and siltstone (aleurolites). At the top of the sub-suite, there are pebbles of raspberry clays and marls. Thickness 80-120 m. The upper sub-suite lies on the lower with signs of erosion and polymictic conglomerates at the base. Above the conglomerates in the section are pinkish light gray cross-bedded sandstones with lenses of green and raspberry clays. The upper part of the sub-suite is composed of fine-grained quartzose pinkish-red sandstones with layers of pinkish-gray clays and siltstone (aleurolites). Thickness 35-71m. In some sections, M. sub-suite reaches 400m.

Lithology Pattern:

Sandstone

Relationships and Distribution

Lower contact

It lies with erosion on the Dzhamsugum Fm or transgressively on the Paleozoic

Upper contact

It is overlain with erosion by the Darbazin Fm or Aksagatin Fm

Regional extent

Pri-Tashkent Chuli, foothills of the Chatkal, Karzhantau, and Kuramin ranges, in the Tashkent depression, revealed by drilling. It is correlated with the Yalovach Fm of Fergana.

GeoJSON

null

Fossils

The upper part of the suite is characterized by the presence of large bivalve remains. The upper sub-suite contains mollusks Sainshandia vernadzkii (Muzaph.), S. sp., Plicatotrigonioides sp.; shark bone remains - Hybodus sp.; turtles - Adocus (?) sp., Sachemys sp., Lindholmemys sp., Trionychidea, Tectudines indet.; crocodiles - Paralligatoridae indet; dinosaurs of three families. Probably, at the base of this layer, G.A. Belenky (96) discovered the skeleton of a duck-billed dinosaur of the family Hadrosauridae. Above the conglomerates are layers of gravelites (0.2 m) yellow with dinosaur bones and mollusks Neotrigonioides kuramensis Mart., Sainshandia kansaica Mart., characteristic of the Santonian. In Kyzylkysay, large mollusk nuclei - Neotrigonioides kuramensis Mart., N. gigantus Mart., Plicatotrigonioides subovalis Kob.

Age

It is conditionally attributed to the upper part of the middle Turonian - Santonian; Along G.A. Belenky, - to the upper Turonian (96); Along the Decision... . . ., 1977 (383), - to the upper Turonian - Santonian; in the Strat. layer (446) - to the upper Turonian - Coniacian; N.E. Minakova (298) included the upper layers of the S. sub-suite in the Lower Darbazin horizon and attributed them to the Turonian.

Age Span:

Beginning stage:

Turonian

Fraction up in beginning stage:

0.8

Beginning date (Ma):

90.29

Ending stage:

Santonian

Fraction up in the ending stage:

1.0

Ending date (Ma):

83.65

Depositional setting

Depositional pattern:

Additional Information

Compiler:

I.M. Abdazimova – In: GeoGPT translation of: “Abduazimova, Z.M. (Ed.), 2001. Stratigraphic Dictionary of Uzbekistan. IMR (Institute of Mineral Resources), Tashkent, 580 pp. (In Russian)”